JPA Tools -> Generate Entities from Tables... results in duplicate fields:
Predictably this results in this:
Not shown are all the duplicated getters and setters. Deleting them is a pain, even for a small class like this.
I cannot see any easy option to fix this. Does anyone have any ideas why it's happening? Thanks in advance.
This is true for mysql. I had three identical schemas with the same user table on mysql database instance. The entity created by the JPA Tools plugin had multiple fields with same name mapped to the multiple user tables in various schemas. Once I deleted all but one schema on the database, the tool retrieved correct list of fields that mapped to columns on the table
I had the same issue. I just renamed the other table in another schema. It seems that the Generate Entities from Table in Eclipse for a MySQL database looks for all tables with the same name no matter the schema.
Related
In the newMips database, the 2 tables user and *_e_user have (almost) the same data. Why? What is the role of each tables?
I guess the answer will help me to understand why the tables role and *_e_role contain different data.
Table user is to manage users of the generator itself.
Table *_e_user is to manage users of generated applications.
I just get a new project that need to work with a DB nobody knows about the structure about it. It is on the Mysql DB so I tried to use mySQL Workbench to export EER Diagram from this DB by using the Reverse Engineer function as many others recommended
I did get tables from the DB...but JUST tables!! no relationship that is the lines connect tables. Did I do something wrong or it is just because the ER Diagram from MySql Workbench is supposed to be like that?
Can anyone recommend tools that can export ER Diagram from existed DB? Include the relationship lines...
Relationships are only shown for foreign keys (how could MySQL Workbench otherwise know). If your tables have no foreign keys (e.g. because they are still using the MyIASM table engine instead of InnoDB) you won't get any relationships.
I have some tables which should add to my database every year and name of databases contains the year (like sell2005) and iv'e written some ef queries on these tables ,and queries can only be on a single entity (like sell2005) but what should i do when sell2006 or sell2007 add ? how can i manage them with that single query which iv'e written before?
thank you.
There is no easy way. EF is simply not tool for this scenario. For EF you must have "single table" so you must either use partitioning with one real database table partitioned by year or you must build a view on top of these tables.
The problem is that in EF you have strict relation between classes and tables. You cannot have single class mapped to multiple tables even if they are exactly same (except inheritance which is not solution for you). So the workaround would require to have multiple SSDL/MSL mappings - one for each table and construct correct context instance with correct mapping for every query. As I know dynamic changes of mapping are not possible (except modifying SSDL/MSL files before using them).
I have tables across 3 different database schemas. JPA confuses itself because it tries to find the table at the wrong schema.
I know I can specify the schema at the #Table annotation but, one of the schemas varies and I can't block it's name.
So, my idea is to tell JPA to always prepend the schema name in the queries it creates, whether I define it or not in the #Table annotation.
Is this possible?
Any other solution?
Thanks!
Note: I'm not using Hibernate, I'm using Toplink.
Use a JPA orm.xml and define the schema/catalog in there in the global section. Works fine with DataNucleus JPA when you do that.
Talk to your DBA to see if he can create a schema that will merge all three schemas. That way your application will only have to deal with one schema. DB2 for zOS can do this and it saved having to create different orm.xml files for each environment.
We have an application that creates new tables at runtime, but always with the same table schema. The only thing that varies from one of these tables to the next is the table name. Is it possible to access these tables using Entity Framework, specifying which table to access by name?
Entity Framework is not designed for DDL, it's an ORM tool for data access. You would want to use a simple ADO.NET query to create/drop the table.
Creating and dropping tables for every user session will make your log file grow very big very fast. I would consider carefully the reasons you think this is necessary. If the data is temporary, why not save the Session ID in each row and truncate the table on a daily basis?
UPDATE:
No, not really. The Entity Data Model is not dynamic, it's a static XML document that describes the structure of the database. If you want to interact with a table with a dynamic name, you're going to have to stick to "classic" ADO.NET.
With Linq to SQL I guess it would be possible with a stored procedure taking the table Name as a parameter.
A nice post about SP in L2SQL: http://weblogs.asp.net/scottgu/archive/2007/08/16/linq-to-sql-part-6-retrieving-data-using-stored-procedures.aspx
I don't know if that feature exists in EF.